Assignee
DIGITAL TELECOMMUNICATIONS SYS
US·8 granted patents·223 citations·filing 1986–1989
Technology mixH04M8
Top patents by PatentIndex Score
8 records- 0178US5161184ARing-back powered telephone with nonvolatile memory structureDIGITAL TELECOMMUNICATIONS SYS·Filed 1989·Granted Nov 3, 1992·57 cites·39 claims
- 0275US4777647APay station telephone interfaceDIGITAL TELECOMMUNICATIONS SYS·Filed 1986·Granted Oct 11, 1988·48 cites·17 claims
- 0374US4947422APersonalized telephone for automatic access to operator servicesDIGITAL TELECOMMUNICATIONS SYS·Filed 1989·Granted Aug 7, 1990·43 cites·52 claims
- 0464US4916733APay station telephone call answer supervision apparatusDIGITAL TELECOMMUNICATIONS SYS·Filed 1988·Granted Apr 10, 1990·25 cites·28 claims
- 0560US4924497APay station telephone interface circuitsDIGITAL TELECOMMUNICATIONS SYS·Filed 1988·Granted May 8, 1990·21 cites·27 claims
- 0654US4942604ALine power control circuit for pay station telephoneDIGITAL TELECOMMUNICATIONS SYS·Filed 1988·Granted Jul 17, 1990·16 cites·26 claims
- 0741US4926468APay station telephone coin box apparatusDIGITAL TELECOMMUNICATIONS SYS·Filed 1988·Granted May 15, 1990·7 cites·20 claims
- 0839US4926469APay station telephone call routing apparatusDIGITAL TELECOMMUNICATIONS SYS·Filed 1988·Granted May 15, 1990·6 cites·13 claims
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Counts cover granted patents and pending applications in the PatentIndex corpus. How scoring works →